Device and associated methods for performing luminescence and fluorescence measurements of a sample

ABSTRACT

Apparatuses and methods of optically analyzing fluid within a pipette are described herein. In an embodiment, an optical reader subassembly includes a housing including an internal area, a container configured to hold a fluid sample at a sample position in a light tight manner within the internal area of the housing, a light source configured to project light onto the fluid sample within the container, and an optical sensor configured to move between different sensor positions while the fluid sample remains stationary at the sample position, the different sensor positions including at least two of: (i) a first sensor position for taking a luminescence reading of the fluid sample; (ii) a second sensor position for taking a dark current or other background measurement; and (iii) a third sensor position for taking a fluorescence reading of the fluid sample.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit as a continuationapplication of U.S. application Ser. No. 14/634,061, filed Feb. 27,2015, entitled “Device and Associated Methods for PerformingLuminescence and Fluorescence Measurements of a Sample”, now U.S. Pat.No. 9,766,233, issued Sep. 19, 2017, which is a continuation of U.S.application Ser. No. 14/215,861, filed Mar. 17, 2014, entitled “Deviceand Associated Methods for Performing Luminescence and FluorescenceMeasurements of a Sample”, now U.S. Pat. No. 9,075,055, issued Jul. 7,2015, which is related to and claims priority to U.S. Provisional PatentApplication Ser. Nos. 61/791,295 and 61/791,879, each of which werefiled on Mar. 15, 2013, the complete and entire disclosures of each ofwhich are hereby expressly incorporated by reference herein.

BACKGROUND OF THE DISCLOSURE

The statements in this section merely provide background informationrelated to the present disclosure and should not be construed asconstituting prior art.

During an automated immunochemistry analysis, analyte molecules in apatient's biological sample (e.g. serum or plasma) attach toparamagnetic particles. To remove background signals associated withpotential chemical sources that may be present in the sample as well, anumber of washing steps are typically implemented into the process. Aconsequence of these washing steps, however, is that some fraction ofthe original particles will be lost for subsequent chemistry processes.

As such, there is a need for a process that allows the particlesremaining after the washing steps to be quantified in order to normalizethe luminescence signal from the patient sample. The present applicationis intended to improve upon and resolve some of these known deficienciesof the art.

SUMMARY OF THE DISCLOSURE

In accordance with one aspect of the present application, a process foroptically measuring a dynamic chemical range of a sample in a reactioncuvette is provided. In accordance with this aspect of the presentdisclosure, the process comprises moving an optical detector from aluminescence reading position within a light tight optics box to afluorescence reading position within the light tight optics box. Bymoving the optical detector to the fluorescence reading position,crosstalk from the fluorescence light source can be minimized.

According to another aspect of the present disclosure, an opticalreading subassembly for an automated immunochemistry analyzer isprovided and comprises an optical pipette configured to aspirate asample from a cuvette as part of a chemistry process on an automatedanalyzer; an opaque optics box, which mates in a light tight manner withthe optical pipette, with a common end and an emission end of abifurcated optical fiber bundle, with a drain tube, and with a multi-pinelectrical power/signal connector; a fluorescence excitation lightsource; a bifurcated fiber optic bundle, one leg of which is connectedto the light source, one leg of which is connected through a series ofemission optical filters to a fluorescence detection port of the opticsbox, and whose common end is connected to the optics box so that it canefficiently illuminate and thereby excite a fluorescent sample in thetip of the optical pipette and simultaneously collect a portion of theemission light from that fluorescent sample; a drain port, which allowsdroplets of fluid from the pipette tip to be removed from the opticsbox, without introducing stray light into the box; an optical detectorwith enough dynamic range to measure both fluorescence and luminescencesignal from the samples; and a shutter mechanism, which can move theoptical detector between a luminescence reading position, a fluorescencereading position, and an optically dark position.

In accordance with another aspect of the present disclosure, anapparatus for measuring the luminescence and the fluorescence of asample is provided and comprises a light tight optics box capable ofreceiving a pipette tip containing a sample; an optical sensor locatedwithin the optics box and capable of being disposed in both aluminescence reading position and a fluorescence reading position; anexcitation light fiber optic bundle and a sample transmission fiberoptic bundle; an excitation light assembly that projects excitationlight onto a first terminus end of the excitation light fiber opticbundle; and an in-line filter located along the sample transmissionfiber optic bundle; wherein the optical sensor observes a luminescencereading from the sample while in the luminescence reading position andthen transfers to the fluorescence reading position to projectexcitation light into one end of the excitation light fiber opticbundle, the excitation light fiber optic bundle being configured totransfer the excitation light onto the sample in the pipette tip; andwherein the transmission fiber optic bundle is configured to transmitthe observed luminescence reading of the sample through the in-linefilter and to the optical sensor disposed in the fluorescence readingposition.

In accordance with still another aspect of the present disclosure, anautomated method for controlling an automated fluorescence andluminescence reading device is provided and comprises the steps ofmoving an optics pipettor from a neutral position to a position within acuvette; aspirating a sample from the cuvette; raising the opticspipettor out of the cuvette and positioning the sample at the tip of theoptics pipettor by aspirating a volume of air; moving the opticspipettor to orient a clear tip of the optics pipettor within theinternal region of an optics box; rotating an optical sensor from asecond position to a first position via an electric motor; measuring andrecording the luminescence reading from the optical sensor; rotating theoptical sensor to a third position; enabling an excitation lightemitting diode to project excitation light onto one terminus end of anexcitation fiber optic bundle; projecting the excitation light from theexcitation fiber optic bundle onto the sample; transmitting an observedreaction through a transmission fiber optic bundle to a transmissionterminus end disposed across from the optical sensor; measuring andrecording the fluorescence reading projected from the transmissionterminus end onto the optical sensor; rotating the optical sensor to thesecond position; measuring and recording a dark reading while theoptical sensor is in the second position; moving the optics pipettorfrom the optics box to a wash station; flushing the sample from theoptics pipettor by dispensing a volume of air; aspirating a systemliquid into the optics pipettor and dispersing the system liquid in awash cycle; and moving the optics pipettor to the neutral position inpreparation for the next sample.

In accordance with yet another aspect of the present disclosure, anautomated fluorescence and luminescence reading machine is provided andcomprises an optics pipettor that has a clear tip, an opaque body, and adisc feature around the opaque body; a pipette transfer arm thattransfers the optics pipettor to a plurality of locations, the pluralityof locations including a read position, a wash position, and a sampleaspiration position; an optics box that can encompass a light tightinternal environment when the optics pipettor is in the read position; adrain port coupled to the optics box, the drain port coupling to a draintube that transfers any excess liquid out of the internal environment; afirst fiber optic transition coupled to the optics box, the first fiberoptic transition creating a light-tight seal to allow a first fiberoptic bundle to expose an emission terminus end inside the internalenvironment; a second fiber optic transition coupled to the optics box,the second fiber optic transition creating a light-tight seal to allow acommon terminus fiber optic bundle to expose a common terminus endinside the internal environment; a stepper motor coupled to a shuttermechanism; an optical sensor coupled to the shutter mechanism, theshutter mechanism and the stepper motor controlling the orientation ofthe optical sensor; an optical alignment plate containing a firstreading position, a second reading position, and a third readingposition; and a reentrant seal on the optics box, the reentrant sealdesigned to partially mate with the disc feature around the opaque bodyof the optics pipettor, a fluorescence excitation assembly that houses alight emitting diode, the light emitting diode configured to transmit afluorescence signal to a terminus end of a fluorescence excitation fiberoptic bundle; wherein when the pipette transfer arm transfers the opticspipettor to the read position, the reentrant seal and the disc featuremay partially mate to one another to prevent light from entering theinternal environment; and wherein when the pipette is in the readposition, the optical sensor may be aligned in the first readingposition where the luminescence reading of a sample within the clear tipmay be measured by the optical sensor and when the optical sensor isaligned in the third reading position where a fluorescence measurementis obtained from the sample in the clear tip through the emissionterminus end of the first fiber optic bundle.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned aspects of the present invention and the manner ofobtaining them will become more apparent and the invention itself willbe better understood by reference to the following description of theembodiments of the invention taken in conjunction with the accompanyingdrawings, wherein:

FIG. 1 is a top schematic view of an automated immunochemistry analyzerand reagent system in accordance with the teachings of the presentapplication;

FIG. 2 is a perspective view of the optical subassembly of the automatedimmunochemistry analyzer and reagent system of FIG. 1;

FIG. 3 is a front side view of a portion of the optical subassembly ofFIG. 2 with a front surface removed;

FIG. 4 is an exploded perspective view of some of the internalcomponents of the portion of the optical subassembly of FIG. 3;

FIG. 5 is a partial section view of the portion of the opticalsubassembly of FIG. 3 with an optical sensor in a first position and anoptical pipettor disposed therein;

FIG. 6 is a partial section view of the portion of the opticalsubassembly of FIG. 3 with the optical sensor in a third position;

FIG. 7 is a partial section view of the portion of the opticalsubassembly of FIG. 3 with a pipettor disposed within the opticalsubassembly;

FIG. 8 is a perspective view of an in-line fiber optic light filterassembly in accordance with the teachings of the present application;

FIG. 9 is an exploded perspective view of the in-line fiber optic lightfilter assembly of FIG. 8.

FIG. 10 is a perspective view of a fluorescence excitation subassemblyin accordance with the teachings of the present application;

FIG. 11 is a section view of the fluorescence excitation subassembly ofFIG. 10;

FIG. 12 is a top side section view of a bifurcated fiber optic cablerouting system in accordance with the teachings of the presentapplication; and

FIG. 13 is a flowchart showing system control logic for the opticalsubassembly of FIG. 2.

Corresponding reference characters indicate corresponding partsthroughout the several views. Although the exemplification set outherein illustrates embodiments of the invention, in several forms, theembodiments disclosed below are not intended to be exhaustive or to beconstrued as limiting the scope of the invention to the precise formsdisclosed.

DETAILED DESCRIPTION

The above-mentioned aspects of the present application and the manner ofobtaining them will become more apparent and the teachings of thepresent application itself will be better understood by reference to thefollowing description of the embodiments of the present application.Moreover, although the exemplification set out herein illustratesembodiments of the present application, in several forms, theembodiments disclosed below are not intended to be exhaustive or to beconstrued as limiting the scope of the present application to theprecise forms disclosed. Rather, the embodiments are chosen anddescribed so that others skilled in the art may appreciate andunderstand the principles and practices of the present application.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this application belongs. Although any method andmaterials similar or equivalent to those described herein can be used inthe practice or testing of the present application, the specific methodsand materials are now described.

FIG. 1 illustrates the various components of an automated diagnosticimmunochemistry analyzer 100 in accordance with the teachings of thepresent disclosure. The automated immunochemistry analyzer 100 can takean analyte sample, create an environment that will allow it to bind to aparamagnetic particle, perform a number of washing steps, then quantifyand normalize the luminescence signal of the analyte sample. This can beaccomplished through an automated process that utilizes a vortexer 102,an R1 pipettor 104, a reaction rotor 106, an optics pipettor 108, anoptics box 110, a multi rinse pipettor 112, a reagent rotor 114, asingle rinse pipettor 116, a sample rotor 118, a sample pipettor 120, anR2 pipettor 122, and a mixed substrate container 124.

To better understand the mechanical aspects of this disclosure, a sampleprocess will be outlined explaining one possible method the apparatuscould utilize to quantify and normalize the luminescence signal of ananalyte sample. Specifically, the automated immunochemistry analyzer 100begins by first dispensing fluorescently labelled paramagneticparticles, or fluo-beads, into a cuvette located within the reactionrotor 106. The fluo-beads may initially be located in the vortexer 102and be transferred to the reaction rotor 106 by the R1 pipettor 104. TheR1 pipettor 104 can aspirate a desired quantity of the fluo-bead mixtureand transfer the aspirated quantity to the reaction rotor 106 where itis injected into the cuvette of the reaction rotor 106. Following theinjection into the cuvette, the optics pipettor 108 may aspirate a testsample from the cuvette of the reaction rotor 106 and transfer the testsample to the optics box 110. Once the sample is disposed within theoptics box 110, fluorescence and luminescence measurements can berecorded. The initial recording of the fluorescence and luminescencesignal can be used as a baseline measurement for the fluorescence signalthat can correspond to the initial concentration of fluo-beads in asample. After recording the measurements, the multi rinse pipettor 112can rinse the cuvettes using a wash buffer.

Next, fluo-beads may be transferred from the vortexer 102 to a cuvettein the reaction rotor 106 via the R1 pipettor 104. Then, the R1 pipettor104 may aspirate a capture reagent from the reagent rotor 114 and injectthe capture reagent into the cuvette located in the reaction rotor 106.After an incubation period, the single rinse pipettor 116 may inject arinse buffer to resuspend the fluo-bead. A substantial amount of thesuspended fluo-bead may then be localized by magnets within the reactionrotor 106 over a period of time. After the magnets have substantiallylocalized the fluo-beads within the cuvette, the multi rinse pipettor112 may aspirate and dispose of a portion of the rinse buffer, leaving aportion of the fluo-beads localized within the cuvette. The multi rinsepipettor 112 may proceed to inject a wash buffer into the cuvette of thereaction rotor 106, resuspending the fluo-beads. The fluo-beads mayagain be localized by the magnets within the reaction rotor 106 to befollowed by the multi rinse pipettor 112 aspirating and discarding aportion of the sample that was not localized from the cuvette in thereaction rotor 106.

A patient sample may be contained in a sample tube on in the samplerotor 118. The patient sample may further be partially diluted with asample diluent. At this point, the sample pipettor 120 may aspirate aportion of the patient sample and inject the patient sample into thecuvette of the reaction rotor 106 to resuspend the fluo-beads. Thecuvette containing the patient sample within the reaction rotor 106 maythen incubate the patient sample. In one embodiment, the incubationtemperature can be about 37 degrees Celsius+/−about 0.2 degree Celsiuswhile the incubation time can be about 37.75 minutes+/−about 2 minutes.After incubation, the single rinse pipettor 116 may inject the rinsebuffer to again resuspend the fluo-beads. Another localization processis performed by the reaction rotor 106 by allowing the fluo-beads tosubstantially collect within the cuvette near the magnets in thereaction rotor 106. After the localization of the fluo-beads, the multirinse pipettor 112 may aspirate and discard a portion of the fluidwithin the cuvette of the reaction rotor 106 that was not localizedduring the localization process.

A couple of rinse cycles may then be performed on the sample within thecuvette of the reaction rotor 106. The rinse cycle may comprise usingthe multi rinse pipettor 112 to inject a wash buffer into the cuvette toresuspend the fluo-beads. Another localization step may allow thefluo-beads to collect within the cuvette by the magnets within thereaction rotor 106. After about a 90 second fluo-beads collectionperiod, the multi rinse pipettor 112 may aspirate and discard a portionof the wash buffer, leaving a substantial portion of the fluo-beadswithin the cuvette of the reaction rotor 106. Another rinse cycle maythen occur by using the multi rinse pipettor 112 to again inject washbuffer into the cuvette and allow the fluo-beads to resuspend. Anotherfluo-bead localization process may utilize the magnets within thereaction rotor 106 to localize the fluo-beads from the rest of thesample. Finally, the multi rinse pipettor 112 may aspirate a portion ofthe sample that was not localized by the localization process.

At this point, the R2 pipettor 122 may aspirate a conjugate contained ina conjugate cuvette within the reagent rotor 114. The R2 pipettor 122may then inject the previously aspirated conjugate into the cuvette ofthe reaction rotor 106. After incubating the cuvette under controlledtime and temperature in the reaction rotor 106, the single rinsepipettor 116 may inject a rinse buffer into the cuvette in the reactionrotor 106. Another fluo-bead localization cycle may be performed byallowing magnets within the reaction rotor 106 to substantially localizethe fluo-beads within the cuvette. The multi rinse pipettor 112 mayaspirate and discard a portion of the sample within the cuvette that hasnot been localized during the localization cycle.

Two more rinse cycles may be performed on the sample within the cuvetteof the reaction rotor 106. The multi rinse pipettor 112 may inject awash buffer to resuspend the fluo-beads within the cuvette. Anotherfluo-bead localization cycle may localize the fluo-beads by locating thecuvette within close proximity to the magnets in the reaction rotor 106over an adequate period of time. After the localization cycle, the multirinse pipettor 112 may aspirate and discard a portion of the sample thatwas not localized during the localization cycle. A second wash cycle maythen occur by using the multi rinse pipettor 112 to inject the washbuffer to resuspend the fluo-beads. Another localization cycle mayutilize the magnets within the reaction rotor 106 to localize thefluo-beads within the cuvette. After the localization process, the multirinse pipettor 112 may again aspirate and discard a portion of thesample that was not localized during the localization cycle.

At this point, the R2 pipettor 122 may aspirate a portion of conjugatefrom the reagent rotor 114 and inject the conjugate into the mixedsubstrate container 124 creating a mixed substrate sample. The R2pipettor may then aspirate the mixed substrate sample from the mixedsubstrate container 124 and inject the mixed substrate sample into thecuvette of the reaction rotor 106, resuspending the fluo-bead with themixed substrate sample. The sample in the cuvette of the reaction rotor106 may then be aspirated by the optics pipettor 108 and placed in theoptics box 110. After the optics box makes fluorescence and luminescenceoptical observations, the sample is discarded and the multi rinsepipettor rinses the cuvettes of the reaction rotor 106 in preparationfor the next test.

Moving now to FIG. 2, an optical subassembly 200 of the automatedimmunochemistry analyzer and reagent system 100 is described in moredetail. More particularly, the optics pipettor 108 is shown coupled to apipette transfer arm 204. The optics pipettor 108 may be composed of asubstantially opaque body 210 and terminate at a substantially clear tip208. Further, the optics pipettor 108 may have a disc feature 212located along the opaque body 210. The optics pipettor 108 and thepipette transfer arm 204 may be mechanically coupled to one another in away that allows the optics pipettor 108 to be transferred to and from aplurality of positions with respect to the automated analyzer 100. Forexample, the optics pipettor 108 could be transferred from the opticsbox 110 to a wash station 224, from the wash station 224 to the reactionrotor 106, from the reaction rotor 106 to the optics box 110, or anycombination thereof.

The optical subassembly 200 is a robotic device that can access acuvette on the reaction rotor 106 of the automated immunochemistryanalyzer 100, aspirate a sample to a controlled position within theoptically clear tip 208, and position the clear tip 208 to a controlledposition within the optics box 110. Except for the clear tip 208, whichis optically clear, the opaque body 210 connected to it is opaque inorder to not introduce stray light into the optics box 110. The discfeature 212 of the opaque body 210 may mate in a reentrant fashion withthe optics box 110 in order to prevent stray light from entering thebox. The opaque body 210 can be any non-compliant material, such as, butnot limited to, black FEP, a black polymer (e.g., Delrin or ABS) thatcan be machined to permit airtight mating with the clear tip 208. Theclear tip 208 can be any optically clear polymer, such as, but notlimited to, polypropylene. While various different materials can be usedfor the clear tip 208, it should be understood and appreciated by thosewithin the art that care should be taken to avoid materials that mightfluoresce or luminesce at the excitation wavelength used in the device.

The pipette transfer arm 204 may be capable of placing the clear tip 208of the optics pipettor 108 at least partially inside the optics box 110,allowing the disc feature 212 to become partially disposed within anoptics pipettor reentrant seal 220 located on the optics box 110. Whenthe disc feature 212 is at least partially disposed within the opticspipettor reentrant seal 220, light is substantially inhibited fromentering the optics box 110.

The optics box 110 is an enclosure with several ports for optical,electrical, and mechanical connections. Care must be taken so that allsuch connections permit no stray light to enter the box. In particular,the port for the optics pipettor 108 has the disc feature 212 that mateswith the reentrant feature of the optics box 110. In one embodiment, theoptics box 110 is made from a polymer material (such as black ABS) thatcan be easily machined to discourage reflectance by surface roughening,painting, or other such means. It may contain features, such as lighttraps or baffles that minimize the stray light entering the opticalsensor. It provides well-defined unobstructed optical paths for thefluorescence and luminescence readings. It has a drain port opaquefitting 336 and tubing 338 that are connected to the optics box 110 andpermits any liquid that might drip from the optics pipettor 108 to pooland be carried away from the region of optical detection (FIG. 3). Theoptics box 110 has a provision for mounting a drive mechanism (such as,but not limited to, a stepper motor) and a sensor for a shuttermechanism. The optics box 110, in accordance with one embodiment, hasdetent features for accurately positioning the optical sensor forluminescence and fluorescence reading.

FIG. 2 further illustrates a fiber optic cable common terminus inlet 214and a fiber optic cable emission terminus inlet 216. Both the fiberoptic cable common terminus inlet 214 and the fiber optic cable emissionterminus inlet 216 can provide a light-sealed transition between theinterior of the optics box 110 and the exterior of the optics box 110for a bifurcated fiber optic cable 1202 (FIG. 12). The fiber optic cableinlets 214, 216 can allow only desired light signals to be distributedinto, and transferred out of the optics box 110.

Further, a shutter stepper motor 218 may be coupled to the optics box110 with a light-tight seal similar to the reentrant seal 220, allowingthe shaft of the shutter stepper motor 218 to be disposed within theinterior of the optics box 110 without allowing any external light topenetrate through the mounting location. One skilled in the art canappreciate the many ways such a seal could be achieved. For example, thebody of the shutter stepper motor 218 could be coupled to the optics boxand a gasket or O-ring could be positioned between the body of theshutter stepper motor 218 and the optics box 110, preventing anyexterior light from entering the interior portion of the optics box 110at the seal. Further, a reentrant seal could utilize a series ofcircular peaks and valleys about the opening on the optics box 110 thatmate to inverse peaks and valleys located on the shutter stepper motor218. One skilled in the art can understand that the light tight sealbetween the shutter stepper motor 218 and the optics box 110 can beachieved many different ways and the present disclosure should not belimited to the particular methods disclosed above.

An electronics communication coupler 222 may also be located on theoptics box 110. The electronics communication coupler 222 can allow anexternal electrical connector to be electronically coupled to anyelectrical devices inside the optics box 110. For instance, theelectronics communication coupler 222 could allow a system controller tobecome electronically coupled too, and thereby control, the electricalcomponents within the optics box 110. Further the electronicscommunication coupler 222 can provide a light tight transition for wiredelectronic signals from the inside of the optics box 110 to the outsideof the optics box 110 or vice versa. The electronics communicationcoupler 222 may also be coupled to the optics box 110 in a plurality ofways that inhibit outside light infiltration. More specifically, theelectronic communication coupler 222 can be coupled to the optics box110 with opaque adhesives that may hold the electronic communicationscoupler 222 in place while simultaneously preventing any exterior lightfrom entering the optics box 110. Further, a gasket or O-ring may bedisposed between the optics box 110 and the electronic communicationscoupler 222 to prevent any external light from entering the interior ofthe optics box 110.

FIG. 3 shows a more detailed view of the optics box 110 with one surfaceremoved. The optics box 110 may be comprised of a first section 302, asecond section 304, a third section 306, a fourth section 308, a fifthsection 310, and a cover section 226 (FIG. 2). Each of the sections 302,304, 306, 308, 310, and 226 may be coupled to one another in a way thatcreates an internal area 322 that is substantially isolated from anyexternal light by implementing any of a plurality of methods forcreating a light-tight seal. One skilled in the art could understand themany possible methods for coupling sections together in a light tightmanner can be utilized in accordance with the present disclosure,whereby the present teachings are not intended to be limited herein. Forinstance, in accordance with certain aspects, a gasket can be placed atevery coupled edge, providing a tongue-and-groove relationship betweenthe sections. Alternatively, the sections could be welded or machined insuch a manner that the infiltration of outside light is substantiallyrestricted.

The drain port opaque fitting 336 in the optics box 110 may be locatedbeneath the optics pipettor 108 so that any liquid dripping from theclear tip 208 could accumulate in or above the drain port opaque fitting336 and be removed from the box by gravity or by an external pumpthrough the tubing 338. To prevent stray light from entering the opticsbox 110, the drain port opaque fitting 336 and tubing 338 can besubstantially resistant to external light permeation. Maintaining thelight tight seal of the internal portion of the optics box 110 mayfurther be achieved by having the tubing 338 extend away from the opticsbox 110 in a corkscrew fashion. The corkscrew path of the tubing 338 mayensure there is no direct path for any external light to shine into thenoptics box 110 through the tubing 338. Further, the interior of thetubing 338 may be made of a non-reflective material that cansubstantially restrict the transmission of light through the interiorportion of the tubing 338. While one embodiment utilizes a corkscrewconfiguration of the tubing 338, one skilled in the art would appreciatehow many tubing configurations could be used to prevent light fromhaving a direct path to the interior of the optics box. For instance, azigzag, semicircular arc, or 90 degree bend among other things could beused in the tubing 338 to restrict light from entering the optics box110 and this disclosure should not be limited to any particularorientation.

The internal area created by the surrounding sections 302, 304, 306,308, 310, and 226 may also contain a shutter mechanism 314, an opticalsensor 316, a shutter sensor 318, and an optical alignment plate 320among other things. The third section 306 may contain the opticspipettor reentrant seal 220 for the optics pipettor 108. The clear tip208 of the optics pipettor 108 may be substantially disposed within theinternal area 322 when the disc feature 212 is at least partiallycoupled to the optics pipettor reentrant seal 220. The disc feature 212may be spaced an appropriate distance from the clear tip 208 to ensurethat when the disc feature 212 contacts the optics pipettor reentrantseal 220 the clear tip 208 will be disposed in a desired location formaking an optical reading. Further, the optics pipettor reentrant seal220 may have a series of circular peaks and valleys that inverselycorrelate with the corresponding portion of the disc feature 212. Whenthe disc feature 212 is at least partially disposed within the opticspipettor reentrant seal 220 of the third section 306, the peaks andvalleys of the disc feature 212 and the optics pipettor reentrant seal220 at least partially couple to one another to substantially block anyexterior light from entering the internal area 322 of the optics box110.

The optical sensor 316 may be coupled to the shutter mechanism 314 whichis in turn coupled to the shutter stepper motor 218. The optical sensor316 may be oriented so that the measurement side of the optical sensor316 is oriented towards the optical alignment plate 320. The opticalsensor 316 can be used to measure both fluorescence and luminescencesignals from a source. In one embodiment, the optical sensor may be aphotomultiplier tube. The optical sensor 316 may also be sensitive tolight and require the internal area 322 to be substantially void of anylight other than the light emitted from the desired source.

The optical alignment plate 320 can contain a plurality of readingpositions for the optical sensor 316. In the embodiment shown in FIG. 3,the optical alignment plate 320 contains three reading positions. Inparticular, a first reading position 326 could be for the luminescencereading of a sample within the clear tip 208. A second reading position328 could be substantially blank and allow for a closed position thatenables dark current and other electronic background measurements to beobtained. A third reading position 330 could be for a fluorescencereading transmitted through fiber optic cables.

Because the luminescence signals from samples may be quite low, a highsensitivity optical detector, such as a photomultiplier tube (PMT), maybe used. In the first reading position 326, or the luminescence readingposition, the PMT is in close proximity to the sample within the cleartip 208 and therefore accepts a significant fraction of the luminescencephotons emitted from the sample. In the third reading position 330, orthe fluorescence reading position, the PMT is in close proximity to oneend of the receiving fiber bundle and captures most of the emissionlight emanating from its tip. In addition to the fluorescence andluminescence reading positions, the PMT can be placed in the secondreading position 328, or an optically isolated position, where darkcurrent and other electronic background measurements can be obtained.

The optical sensor 316 could be transitioned to and from each of thereading positions 326, 328, and 330 by the shutter mechanism 314. Theshutter mechanism 314 could be coupled to a stepper motor, a pneumaticarm, or any other comparable mechanism that could allow for the movementof the optical sensor 316. The shutter mechanism 314 may also be incommunication with the shutter sensor 318. The shutter sensor 318 maymonitor the orientation of the shutter mechanism 314 and confirm ordictate desired movements of the shutter mechanism 314. The shuttersensor 318 can confirm that the optical sensor 316 is accurately alignedwith any one of the plurality of reading positions 326, 328, and 330 onthe optical alignment plate 320.

To further facilitate accurate optical readings, a cam system can beutilized between the shutter mechanism 314 and the optical alignmentplate 320. The cam system can allow the optical sensor 316 to beseparated from, and coupled to, a reentrant seal located at each of thereading positions 326, 328, and 330 as the optical sensor 316transitions from one reading position to the other. The cam system canincorporate a U-shaped channel 332 disposed within the surface of theoptical alignment plate 320. The U-shaped channel 332 can follow an arcalong the surface of the optical alignment plate 320 that is concentricwith the pivotal center of the shutter stepper motor 218 shaft. TheU-shaped channel 332 may further have a detent or detents 334 located atthe second reading position 328 and the third reading position 330. Thedetent or detents 334 may create a slightly greater recess in theoptical alignment plate 320 than does the U-shaped channel 332. Whileone embodiment may only show the detent or detents 334 at the secondreading position 328 and the third reading position 330, one skilled inthe art can understand how the first reading position 326 could alsohave a detent and a U-shaped channel leading thereto.

FIG. 4 shows the shutter assembly 314 in an exploded view with theoptics box 110 removed. The optical alignment plate 320 may be pivotableabout a pivot pin 404. Further, the pivot pin 404 may be coupled to theinterior portion of the fifth section 310 by a pivot pin retention plate406. The relationship between the pivot pin 404, the pivot pin retentionplate 406, and the optical alignment plate 320 could be such that theoptical alignment plate 320 may rotate about the axis of the pivot pin404. The optical alignment plate 320 may also be coupled to one or morespring 408. The one or more spring 408 may have a first end that iscoupled to the optical alignment plate 320 at a location on the oppositeside as the U-shaped channel 332 and a second end that is coupled to aninterior portion of the fifth section 310.

The U-shaped channel 332 may interact with a cam pin 402 located on ashutter mechanism coupler 412 to maintain the particular orientationbetween the optical alignment plate 320 and the optical sensor 316. Morespecifically, when the cam pin 402 is disposed in the U-shaped channel332, the cam pin 402 may maintain a slight gap between the opticalalignment plate 320 and the optical sensor 316. However, when the campin 402 enters the detent or detents 334, the optical alignment plate320 may rotate towards the optical sensor 316 about the axis of thepivot pin 404. Once the cam pin 402 is at least partially located in thedetent or detents 334, the optical alignment plate 320 may becomeoriented a sufficient distance from the optical sensor 316 to allow theoptical sensor 316 to contact a photo sensor seal 410 around any of thefirst, second, or third reading positions 326, 328, and 330. As theshutter mechanism 314 repositions the optical sensor 316, the cam pin402 may exit the detent or detents 334 and slightly rotate the opticalalignment plate 320 away from the optical sensor 316 about the pivot pin404 axis. The transition of the cam pin 402 out of the detent or detents334 and into the U-shaped channel 332 may slightly compress the one ormore spring 408 and allow the optical sensor 316 to no longer contactthe photo sensor seal 410. The cam pin 402 may then continue to movealong the U-shaped channels 332 of the optical alignment plate 320 untilit reaches the next detent or detents 334. Further, while in theembodiment of the shutter mechanism 314 no detent is shown to orient theoptical sensor 316 in the first reading position 326, the opticalalignment plate 320 may terminate at a location that allows the cam pin402 to become disposed off of the optical alignment plate 320 when theoptical sensor is in the first reading position 326. Similarly to movinginto and out of the detent or detents 334, the cam pin may move off of,or on to the optical alignment plate 320 to orient the optical sensor316 between the reading positions 326, 328, and 330.

The shutter mechanism 314 may be coupled to the shutter stepper motor218 by a hub 414. The hub 414 may be substantially cylindrical with aninner through hole that may be slightly greater than a stepper motorshaft 416 outer diameter. The hub 414 may also have a means forcompressibly coupling the hub 414 to the stepper motor shaft 416.Further, the hub 414 may have at least one through hole that is parallelto the inner through hole that allow the hub 414 to be removably coupledto the shutter mechanism 314. When the hub 414 is compressibly coupledto the stepper motor shaft 416, and the shutter mechanism 314 is coupledto the at least one through hole of the hub 414, the shutter steppermotor 218 may substantially control the movement of the shuttermechanism 314.

The end of the shutter mechanism 314 that is opposite of the hub 414 maybe coupled to the shutter mechanism coupler 412. The shutter mechanismcoupler 412 may further couple the optical sensor 316 to the shuttermechanism 314. Finally, the cam pin 402 may be coupled to a shuttermechanism coupler 312 to ensure proper alignment between the opticalalignment plate 320 and the optical sensor 316. The shutter mechanism314 can allow the optical sensor 316 to measure luminescence andfluorescence signals from a single sample while minimizing cross-talkfrom the fluorescence excitation light source.

FIG. 5 illustrates a partial cross section view 500 of the opticalsensor 316 in the first reading position 326 with the disc feature 212of the optics pipettor 108 at least partially coupled to the opticspipettor reentrant seal 220. In the first reading position 326, theoptical sensor 316 may be disposed in a close proximity to the clear tip208 of the optics pipettor 108. The optical alignment plate 320 may alsohouse the photo sensor seal 410 and a neutral density optical filter 502at the first reading position 326. The neutral density optical filter502 may be disposed between the clear tip 208 and the optical sensor 316where the neutral density optical filter 502 may adjusts the opticalsignals to be in the optical dynamic range of the optical sensor 316.

The close proximity of the optical sensor 316 to the clear tip 208 mayallow the optical sensor 316 to analyze the luminescence of a samplelocated within the clear tip 208 of the optics pipettor 108. During theluminescence reading, it is crucial that the amount of background lightis reduced to a minimum. Background light can be any undesired lightthat may enter the optics box 110 from an external source. Bysubstantially limiting the amount of background light permitted into theoptics box 110, the consistency and accuracy of the luminescence readingis greatly enhanced. FIG. 5 more clearly illustrates how the discfeature 212, the optics pipettor reentrant seal 220, and the opaque body210 can substantially reduce the amount of background light that mayenter the optics box 110 when the optics pipettor 108 is locatedtherein.

In the second reading position 328, the optical sensor 316 may besubstantially disposed in a closed position wherein the opticalalignment plate 320 does not contain a through hole and thereby blocksthe reading end of the optical sensor 316. In the second readingposition 328, the optical sensor 316 may be substantially isolated fromany form of illumination. This reading position may be advantageousbecause it may allow for dark current and other electronic backgroundmeasurements to be obtained and used to aid in the calibration andaccuracy of the desired measurements.

FIG. 6 shows a perspective partial sectional view 600 with the opticalsensor 316 in the third reading position 330. FIG. 12 further shows howin the third reading position 330, the bifurcated fiber optic cable 1202may be utilized to distribute fluorescence excitation light to and fromdesired locations 1200. More specifically, the bifurcated fiber opticcable 1202 may consist of a plurality of fiber optic fibers and may havean emissions fiber optic cable bundle 1216 that connects a commonterminus end 1206 to a fluorescence excitation emission end 1204.Further, a first transmission fiber optic cable bundle 1214 can connectthe common terminus end 1206 to a fiber optic filter housing 1212, whilea second transmission fiber optic cable bundle 1215 can connect thefiber optic filter housing 1212 to a transmission end 1208. The commonterminus end 1206 may be composed of a random configuration of fiberoptic fibers from both the fluorescence excitation emission end 1204 andfiber optic fibers from the transmission end 1208. Further, in oneembodiment there may be slightly more fiber optic fibers in thetransmission end 1208 than in the fluorescence excitation emission end1204. FIG. 6 shows how in the third reading position 330, the opticalsensor 316 can be aligned with the terminus portion of the transmissionend 1208 of the bifurcated fiber optic cable 1202. This alignment mayallow the optical sensor 316 to accurately read the transmissions of thetransmission end 1208 of the bifurcated fiber optic cable 1202.

The fluorescence excitation emission end 1204 can be at least partiallydisposed within a fluorescence excitation emission source housing 1210.The fluorescence excitation emission source housing 1210 could house asystem for emitting a fluorescence excitation light source onto thefluorescence excitation emission end 1204 of the bifurcated fiber opticcable 1202. When fluorescence light is emitted onto the fluorescenceexcitation emission end 1204, the fluorescence excitation light may betransferred through the bifurcated fiber optic cable 1202 to the commonterminus end 1206. At the common terminus end 1206, the fluorescenceexcitation light may be projected onto a sample located within the cleartip 208 of the optics pipettor 108.

FIG. 7 illustrates how fluorescence excitation light enters the opticsbox 110. FIG. 7 shows a partial section view 700 of the optics box 110with the optics pipettor 108 disposed therein. When the optics pipettor108 is disposed within the optics box 110, the clear tip 208 may belocated within close proximity to the common terminus end 1206 of thebifurcated fiber optic cable 1202. The proximity of the common terminusend 1206 to the clear tip 208 within the optics box 110 may allow thefluorescence excitation light emitted from the common terminus end 1206to be projected onto a sample located within the clear tip 208. Whenfluorescence excitation light is projected onto a sample within theclear tip 208, a response reaction may occur within the sample. Forinstance, the fluo-beads in the clear tip 208 may have a fluorescentlabel bound to them. The molecules in the label can absorb theexcitation light energy which may raise the molecular energy state. Theexcited states may spontaneously deexcite to produce the fluorescentlight that the optical sensor 316 detects.

The portion of the common terminus end 1206 that comes from thetransmission end 1208 of the bifurcated fiber optic cable 1202 maycapture the response reaction of the sample within the clear tip 208when the fluorescence excitation light is projected thereon. The visualaspects of the response reaction may be transferred from the commonterminus end 1206, through the fiber optic filter housing 1212, and outof the transmission end 1208 where it can be observed by the opticalsensor 316. To ensure that the transmission end 1208 is not transferringunwanted reflected fluorescence excitation light at the common terminusend 1206, a light trap 702 may be located behind the clear tip 208relative to the common terminus end 1206.

The light trap 702 may substantially inhibit any fluorescence excitationlight projected from the common terminus end 1206 from being reflectedoff of the interior surfaces of the optics box 110 and into the firsttransmission fiber optic bundle 1214 of the common terminus end 1206.The light trap 702 may prevent reflection of the fluorescence excitationlight by allowing any residual fluorescence excitation light notabsorbed by the sample within the clear tip 208 to enter the light trap702 through a light trap opening 704. After fluorescence excitationlight enters the light trap opening 704, a diverter 706 may disperse thefluorescence excitation light about an interior region 708 of the lighttrap 702. The diverter 706 and the interior region 708 can be comprisedof a substantially non-reflective surface that prevents any lightintroduced into the light trap 702 from being reflected out of the lighttrap 702.

FIGS. 10 and 11 illustrate the fluorescence excitation source. Moreparticularly, FIG. 10 shows a perspective view of a fluorescenceexcitation assembly 1000. The fluorescence excitation assembly 1000 ismounted in a separate enclosure from the optics box 110. In accordancewith one aspect of the present disclosure, the light source is ahigh-powered LED with spectral output that will efficiently excite afluorescent label on paramagnetic particles within a sample, althoughother light sources, such as lasers or laser diodes can be used as well.A lens, mounted to an LED circuit board, can focus the light onto theend of a fiber optic bundle. Before entering the fiber, the excitationlight can pass through a narrow band pass optical filter so thatout-of-band light, a potential source of background radiation, can begreatly reduced. The optical fibers in the fiber bundle can have arelatively low numeric aperture in order to greatly reduce the amount ofwide angle excitation light that might impinge on the sample andcontribute to backgrounds. A silicon photodiode in the excitation lightsource can be used to monitor the light intensity of the LED. A passiveheat sink can be attached to the light source to keep the temperaturewithin its nominal operating range.

In more detail of one embodiment, the fluorescence excitation assembly1000 may comprise of a body 1002, a first cover 1004, a first fiberoptic cover 1006, a second fiber optic cover 1008, a control board 1010,and a heat sink 1012. The fluorescence excitation emission end 1204 ofthe bifurcated fiber optic cable 1202 may terminate within the body 1002of the fluorescence excitation assembly 1000. Further, the first andsecond fiber optic covers 1006, 1008, may couple the fluorescenceexcitation emission end 1204 of the bifurcated fiber optic cable 1202 tothe fluorescence excitation assembly 1000. The first and second fiberoptic covers 1006, 1008 may be substantially U-shaped plates that areparallel to one another and oriented 180 degrees to one another. Thisparticular orientation may allow the first and second fiber optic covers1006, 1008 to couple the bifurcated fiber optic cable 1202 to thefluorescence excitation assembly 1000 without allowing any externallight into, or out of, the interior region of the fluorescenceexcitation assembly 1000.

FIG. 11 shows an expanded view 1100 of the fluorescence excitationassembly 1000. The interior region of the body 1002 may further house alight sensor 1102, an excitation O-ring 1104, an excitation light filter1106, an excitation lens 1108, and a light-emitting diode (LED) 1110.The LED 1110 may be positioned with one surface substantially contactingthe heat sink 1012 and with a light-emitting portion substantiallyfacing the interior region of the body 1002. The LED 1110 may be coupledto the heat sink 1012 with a thermal coupling compound that allows asubstantial amount of the heat generated by the LED 1110 to betransferred to the heat sink 1012. The heat sink 1012 can maintain adesired operating temperature of the LED 1110.

The LED 1110 may be oriented to emit light through the excitation lens1108. The excitation lens 1108 may in turn focus the light emitted bythe LED 1110 so that it is substantially directed onto the fluorescenceexcitation emission end 1204 of the bifurcated fiber optic cable 1202.Before the light emitted by the LED 1110 enters the bifurcated fiberoptic cable 1202, it may pass through the excitation light filter 1106.The excitation light filter 1106 may be a fluorescence excitation filterthat corresponds with an excitation spectrum of the fluo-bead samplelocated within the clear tip 208 at the common terminus end 1206.Further, the excitation O-ring 1104 may be positioned within theinterior region of the body 1002 between a holder 1114 and theexcitation light filter 1106. The O-ring may maintain the correctposition of the light filter with respect to the LED 1110 and theemissions fiber optic cable bundle 1216.

The light sensor 1102 may be coupled to the first cover 1004 andoriented to allow the light sensor 1102 to measure the light emissionsin the interior region of the fluorescence excitation assembly 1000. Thelight sensor 1102 may be disposed behind the holder 1114. Further, theholder 1114 may have a light path through hole 1116 that substantiallycorresponds to the location of the light sensor 1102 and allows thelight sensor 1102 to substantially observe the state of the LED 1110.The light sensor 1102 may also be electronically coupled to the controlboard 1010. The control board 1010 may monitor measurements observed bythe light sensor 1102 to determine the fluorescence excitationassembly's 1000 interior conditions. For example, the light sensor 1102may be utilized by the control board 1010 to determine whether LED 1110is emitting light. Further, the light sensor 1102 could be used todetermine and regulate the intensity of the light emitted by the LED1110. The control board 1010 can further be in electronic communicationwith a system control that may control the intensity and timing of theLED 1110.

According to one embodiment in accordance with the present disclosure,the optical system utilizes a bifurcated fiber optic bundle, whichincludes two fiber optic bundles tied together at a common terminusproximal to the optical sample with one bundle transmitting fluorescenceexcitation light from a light source to the sample, and with the otherbundle receiving fluorescence emission light from the sample at thecommon terminus and transmitting that light to an optical detector. Inanother embodiment, the fiber optics may include two separate fiberoptic bundles, one to transmit excitation light from source to sample,and the other oriented at an angle, such as, for instance, 90.degree.,with respect to the excitation bundle, for receiving the fluorescenceemission light and transmitting it to the optical detector.

The first and second transmission fiber optic cable bundle 1214, 1215may utilize fiber optic cables to connect the common terminus end 1206to the transmission end 1208. However, between the common terminus end1206 and the transmission end 1208 is the fiber optic filter housing1212. FIGS. 8 and 9 illustrate with more detail the fiber optic filterhousing 1212. FIG. 8 specifically shows a perspective view 800 of thefiber optic filter housing 1212 and how the fiber optic filter housing1212 can be placed in-line with the first and second transmission fiberoptic cable bundle 1214, 1215. Further, the fiber optic filter housing1212 may have an output end 802 and an input end 804. The input end 804may be an input location where transmissions along the firsttransmission fiber optic cable bundle 1214 are input into the fiberoptic filter housing 1212. Accordingly the output end 802 of the fiberoptic filter housing 1212 may be an output location where transmissionsare output to the second transmission fiber optic cable bundle 1215.

FIG. 9 is an exploded view 900 of the fiber optic filter housing 1212.The input end 804 illustrates how the first transmission fiber opticcable bundle 1214 can enter the fiber optic filter housing 1212. Moreparticularly, a first entrance plate 902 and a second entrance plate 904may substantially couple the first transmission fiber optic cable bundle1214 to the fiber optic filter housing 1212. Both the first and thesecond entrance plate 902, 904 may be substantially U-shaped and providea central cavity that is substantially sized to allow the firsttransmission fiber optic cable bundle 1214 to be disposed therein.Further, the first entrance plate 902 may be parallel to and concentricwith the second entrance plate 904 with the U-shaped portions beingoriented 180 degrees opposite of one another. The 180 degree orientationof the first and second entrance plate 902, 904 can create asubstantially circular through hole through the center of the first andsecond entrance plates 902, 904 when they are coupled to one another.The through hole may be substantially the same diameter as a crosssection of the first transmission fiber optic cable bundle 1214.

After the first and second entrance plate 902, 904, there may be anentrance seal retention plate 906. The entrance seal retention plate 906may have a through hole that is concentric with the first and secondentrance plate 902, 904. Further, the entrance seal retention plate 906through hole may be substantially the same size as the first and secondentrance plate 902, 904 through hole. The entrance seal retention plate906 through hole may also correspond with an entrance O-ring 908. Theentrance O-ring 908 may have a diameter large enough to allow theentrance O-ring 908 to encircle the first transmission fiber optic cablebundle 1214. The entrance O-ring 908 may further become disposed betweenthe entrance seal retention plate 906 and an entrance end cap 910.

The entrance end cap 910 may also have a first partial through holesufficiently sized to allow the first transmission fiber optic cablebundle 1214 to be substantially disposed therein. The first partialthrough hole may be sized to terminate at a second partial through holethat may have a slightly smaller diameter than the first partial throughhole. The first and second partial through holes of the entrance end cap910 may allow the first transmission fiber optic cable bundle 1214 to besubstantially located within, but not all the way through, the entranceend cap 910. Further, the first transmission fiber optic cable bundle1214 may fit into the entrance end cap 910 until it contacts the secondpartial through hole. The slightly smaller diameter of the secondpartial through hole may ensure that the first transmission fiber opticcable bundle 1214 is correctly positioned within the fiber optic filterhousing 1212 while simultaneously allowing the first transmission fiberoptic cable bundle 1214 to project a light source through the fiberoptic filter housing 1212. To accommodate the entrance O-ring 908, theentrance end cap 910 may also have a recessed portion that allows theentrance O-ring 908 to be at least partially disposed within therecessed portion when the entrance seal retention plate 906 is coupledto the entrance end cap 910.

Regarding the input end 804, the first transmission fiber optic cablebundle 1214 may be disposed within the through hole of the entrance endcap 910. Further, the entrance O-ring 908, the entrance seal retentionplate 906, and the first and second entrance plate 902, 904 may becoupled to the entrance end cap 910 with the first transmission fiberoptic cable bundle 1214 disposed therein. The entrance O-ring 908 cansubstantially seal the first transmission fiber optic cable bundle 1214to the entrance end cap 910. The entrance end cap 910 may further becoupled to the fiber optic filter housing 1212. When the firsttransmission fiber optic cable bundle 1214 is disposed within theentrance end cap 910, the entrance O-ring 908, the entrance sealretention plate 906, and the first and second entrance plate 902, 904,the first transmission fiber optic cable bundle 1214 may be held insubstantially concentric alignment with a central axis 912.

After the entrance end cap 910, a first internal O-ring 914, a firstfilter 916, a first aperture 918, a lens holder 920, a lens 922, asecond aperture 924, a third aperture 926, a second filter 928, a thirdfilter 930 and a second internal O-ring 932 may all be disposed withinthe fiber optic filter housing 1212. Following the entrance end cap 910,the first internal O-ring 914 can ensure the first filter 916 remainsdisposed in alignment with the first transmission fiber optic cablebundle 1214. After the first filter 916, the lens holder 920 may holdthe first aperture 918. The lens holder 920 may be threaded about itsexterior surface that allows the lens holder 920 to be coupled to acorresponding threaded interior surface of the fiber optic filterhousing 1212. Further, the lens 922 may be disposed within the fiberoptic filter housing 1212 so that it may be seated against an internalretention shelf of the fiber optic filter housing 1212. After the lens922 is seated against the internal retention shelf, the lens 922 holdermay be threadably coupled to the fiber optic filter housing 1212,thereby retaining the lens 922 against the internal retention shelf.

Following the lens 922 and within the fiber optic filter housing 1212may be the second aperture 924, the third aperture 926, the secondfilter 928, the third filter 930, and the second internal O-ring 932.The second and third apertures 924, 926 may be substantially circularand contain through holes. The second aperture 924 may have a slightlysmaller external diameter than the third aperture 926. Further the fiberoptic filter housing 1212 may have corresponding diameter partialthrough holes that allow the second and the third apertures 924, 926 tobe particularly spaced within the fiber optic filter housing 1212 asthey are placed within the corresponding partial through hole.

Next may be the second and third filter 928, 930. The second and thirdfilter 928, 930 may be maintained within the fiber optic filter housing1212 at least partially by the second internal O-ring 932 that maycontact an exit cap 934. The exit cap 934 may be located at the outputend 802 of the fiber optic filter housing 1212. Similarly to the inputend 804, the output end 802 may have an exit O-ring 936 that can sealthe second transmission fiber optic cable bundle 1215 at the output end802. The exit O-ring 936 can seal the second transmission fiber opticcable bundle 1215 by coupling the second transmission fiber optic cablebundle 1215 to the exit cap 934 with an exit seal retention plate 938,and a first and second exit plate 940, 942. The output end 802 canretain the second transmission fiber optic cable bundle 1215 inalignment with the fiber optic filter housing 1212 in substantially thesame way as the input end 804. In one embodiment, the three filters 916,928, and 930 may be a notch filter to remove the excitation light, along pass filter to eliminate the luminescence signal, and an emissionfilter to further reduce any out of band or wide angle light from thefluorescence emission signal.

FIG. 12 shows how one embodiment of the present disclosure transmitslight from one source to a common terminus via fiber optics, projectsthat light onto a sample, observes the sample's optical response throughfiber optic cables, filters the observed response and transmits thefiltered light to an optical reader. More particularly, the LED 1110 caninitially produce a fluorescence excitation light. The light may thenpass through the excitation lens 1108 where the light is focused forprojection onto one terminus end of the emissions fiber optic cablebundle 1216. Prior to entering the terminus end of the emissions fiberoptic cable bundle 1216, the excitation light filter 1106 may filter thelight produced by the LED 1110 to promote fluorescence excitation. Thefiltered light may be carried through the emissions fiber optic cablebundle 1216 to the common terminus end 1206 where it may be projectedonto a sample located within the clear tip 208. When the fluorescenceexcitation light is projected onto the sample, the light may react withthe sample to emit a visual response.

The visual response of the sample may be captured by the firsttransmission fiber optic cable bundle 1214 at the common terminus end1206. The visual response may further travel through the firsttransmission fiber optic cable bundle 1214 from the common terminus end1206 to the fiber optic filter housing 1212. At the fiber optic filterhousing 1212, the visual response is projected through the first filter916, which may be a notch filter that can attenuate undesiredfrequencies from the visual response, and the first aperture 918 ontothe lens 922. The lens 922 may further modify the visual response andproject the signal through the second and third aperture 924, 926, andthrough the second and third filter 928, 930. After the visual responsehas passed through the second and third filter 928, 930, the filteredvisual response may be projected onto the output terminus of the secondtransmission fiber optic cable bundle 1215.

The second transmission fiber optic cable bundle 1215 may then carry thefiltered visual response to the transmission end 1208 terminus. Thetransmission end 1208 terminus may be disposed within close proximityto, and in alignment with, the optical sensor 316 when the opticalsensor 316 is in the third reading position 330. The transmission end1208 of the second transmission fiber optic cable bundle 1215 may thanproject the readings observed from the sample within the clear tip 208to the optical sensor 316.

FIG. 13 illustrates how the pipette transfer arm 204, the shutterstepper motor 218, the shutter sensor 318, the optical sensor 316, theLED 1110, and the light sensor 1102 may be electrically coupled too, andcontrolled by, a system controller 1300. The method of controlling theautomated analyzer 100 can initially begin with orienting the pipettetransfer arm 204 in a neutral position. From the neutral position, in afirst step 1302, the system controller may move the pipette transfer arm204 to orient the optics pipettor 108 in a position inside a cuvettelocated in the reaction rotor 106. After the system controller hasexecuted the first step 1302, it may send a command to the opticspipettor 108 to aspirate a volume of a sample from the cuvette in asecond step 1304. The system controller may then withdraw the opticspipettor 108 from the cuvette in a third step 1306. While the opticspipettor 108 is located above the cuvette, in a fourth step 1308 thesystem controller may command the optics pipettor to aspirate a volumeof air to position the sample in the clear tip 208. Once the sample ispositioned in the clear tip 208, the system controller may move theoptics pipettor 108 to a location so that the clear tip 208 is disposedwithin the optics box 110 in a fifth step 1310.

After the system controller has obtained a sample within the clear tip208 and positioned the clear tip 208 within the optics box 110, thesystem controller may send a signal to the shutter stepper motor 218 andthe shutter sensor 318 to transition the optical sensor 316 from thesecond reading position 328 to the first reading position 326 per asixth step 1312. In a seventh step 1314, the system controller mayobtain a luminescence reading from the sample by recording inputs fromthe optical sensor 316. After obtaining the luminescence reading in theseventh step 1314, the system controller may send a command to thestepper motor 218 and the shutter sensor 318 to transition the opticalsensor 316 to the third reading position 330 in an eighth step 1316.

After the optical sensor 316 is oriented to the third reading position330, the system controller may enable the LED 1110 to emit fluorescenceexcitation light in a ninth step 1318. The system controller may givethe LED 1110 substantial time to stabilize before the system controllerwill count optical sensor 316 pulses in a time interval 1320. In oneembodiment, it may take about 10 milliseconds for the LED 1110 tostabilize and the optical sensor 316 may take readings for 100milliseconds. Simultaneously with step 1320, in step 1321 the lightsensor 1102 may read the LED 1110 reference signal in a time interval.After the system controller has obtained the necessary fluorescencereadings from the optical sensor 316 in the tenth step 1320 or theeleventh step 1321, the system controller may execute a twelfth step1322 where it commands the stepper motor 218 and the shutter sensor 318to orient the optical sensor 316 in the second position 328.

After the optical sensor 316 is located in the second position 328, in athirteenth step 1324 the system controller may withdraw the opticspipettor 108 from the optics box 110 and transfer the optics pipettor108 to the wash station 224. While the optics pipettor 108 is located atthe wash station 224, the system controller may send a command to theoptics pipettor 108 to flush the sample by dispensing a volume of airduring a fourteenth step 1326. After the sample has been flushed fromthe optics pipettor 108, the system controller may execute a wash cycleduring a fifteenth step 1328 where the optics pipettor 108 utilizes asystem liquid to wash the optics pipettor 108 clear tip 208. The systemcontroller may execute a final air aspiration in a sixteenth step 1330to remove any remaining system liquid from the clear tip 208. Finally,the system controller may move the optics pipettor 108 back to a neutralposition in anticipation for the next cycle during a seventeenth step1332.

The system controller can execute the commands shown in FIG. 13utilizing a plurality of forms known by those skilled in the art. Thesystem controller can execute commands on a time scale with predefinedintervals for each command performed by the system controller. Thesystem controller could also utilize the various sensors locatedthroughout the system to determine the appropriate time to move to thenext step. For instance, the shutter sensor 318 may communicate to thesystem controller when the shutter mechanism 314 is in the correctorientation, at which point the system controller may initiate a timesequence prior to transitioning to the next step. One skilled in the artcould understand the many ways the system controller could control theautomated analyzer 100 such as time sequence commands, proximitysensors, optical sensors, and the like and this disclosure should not belimited to any one embodiment.

While an exemplary embodiment incorporating the principles of thepresent application has been disclosed hereinabove, the presentapplication is not limited to the disclosed embodiments. Instead, thisapplication is intended to cover any variations, uses, or adaptations ofthe application using its general principles. Further, this applicationis intended to cover such departures from the present disclosure as comewithin known or customary practice in the art to which this presentapplication pertains and which fall within the limits of the appendedclaims.

The terminology used herein is for the purpose of describing particularillustrative embodiments only and is not intended to be limiting. Asused herein, the singular forms “a”, “an” and “the” may be intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. The terms “comprises,” “comprising,” “including,” and“having,” are inclusive and therefore specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof. The method steps, processes, and operations described hereinare not to be construed as necessarily requiring their performance inthe particular order discussed or illustrated, unless specificallyidentified as an order of performance. It is also to be understood thatadditional or alternative steps may be employed.

The invention is claimed as follows:
 1. An optical reader subassemblycomprising: a housing including an internal area; a container configuredto hold a fluid sample at a sample position, placement of the containerwithin the housing creating a light tight seal for the fluid sample atthe sample position within the internal area of the housing; a lightsource configured to project light onto the fluid sample within thecontainer; and an optical sensor configured to move between differentsensor positions while the fluid sample remains stationary at the sampleposition, the different sensor positions including (i) at least one of afirst sensor position for taking a luminescence reading of the fluidsample or a third sensor position for taking a fluorescence reading ofthe fluid sample, and (ii) a second sensor position that is opticallyisolated from the fluid sample for taking a dark current or otherbackground measurement even when the light source is projecting lightonto the fluid sample.
 2. The optical reader subassembly of claim 1,wherein the different sensor positions include each of the first sensorposition, the second sensor position and the third sensor position. 3.The optical reader subassembly of claim 1, wherein the optical sensor isattached to a mechanism that moves the optical sensor between thedifferent sensor positions.
 4. The optical reader subassembly of claim3, wherein the mechanism pivots the optical sensor between the differentsensor positions.
 5. The optical reader subassembly of claim 3, whereinthe mechanism includes a cam.
 6. The optical reader subassembly of claim1, which includes an alignment plate, wherein the optical sensor movesalong the alignment plate to move between the different sensorpositions.
 7. The optical reader subassembly of claim 1, wherein thecontainer is a pipette.
 8. An optical reader subassembly comprising: ahousing including an internal area; a container configured to hold afluid sample at a sample position, placement of the container within thehousing creating a light tight seal for the fluid sample at the sampleposition within the internal area of the housing; a light sourceconfigured to project light onto the fluid sample within the container;and an optical sensor configured to move between a first sensor positionto take a luminescence reading, a second sensor position to take afluorescence reading, and a third sensor position that is opticallyisolated from the fluid sample to take a dark current or otherbackground measurement while the fluid sample remains stationary at thesample position even when the light source is projecting light onto thefluid sample.
 9. The optical reader subassembly of claim 8, wherein theoptical sensor is attached to a mechanism that moves the optical sensorbetween the sensor positions.
 10. The optical reader subassembly ofclaim 8, which includes an alignment plate, wherein the optical sensormoves along the alignment plate to move between the sensor positions.11. The optical reader subassembly of claim 10, wherein the opticalsensor is attached to a mechanism that moves the optical sensor alongthe alignment plate.
 12. The optical reader subassembly of claim 9,further comprising a system controller configured to cause the mechanismto move the optical sensor between the different sensor positions,wherein the system controller is configured to record a calibrationmeasurement with the optical sensor in the third sensor position aftercausing the mechanism to move the optical sensor to the third sensorposition from at least one of the first sensor position or the secondsensor position.
 13. The optical reader subassembly of claim 12, whereinthe system controller is configured to cause the light source to emitfluorescence excitation light if the system controller causes themechanism to move the optical sensor to the second sensor position. 14.The optical reader subassembly of claim 8, wherein the container is apipette.
 15. The optical reader subassembly of claim 1, furthercomprising a fiber optic cable with a first end positioned to receivefluorescence light that is emitted by the fluid sample and a second endpositioned to emit the received fluorescence light at the third sensorposition.
 16. The optical reader subassembly of claim 1, wherein theoptical sensor includes a photomultiplier tube (“PMT”).
 17. The opticalreader subassembly of claim 3, further comprising a system controllerconfigured to cause the mechanism to move the optical sensor between thedifferent sensor positions, wherein the system controller is configuredto record a calibration measurement with the optical sensor in thesecond sensor position before causing the mechanism to move the opticalsensor from the second sensor position to at least one of the firstsensor position or the third sensor position.
 18. The optical readersubassembly of claim 17, wherein the system controller is configured tocause the light source to emit fluorescence excitation light if thesystem controller causes the mechanism to move the optical sensor to thethird sensor position.
 19. The optical reader subassembly of claim 8,further comprising a fiber optic cable with a first end positioned toreceive fluorescence light that is emitted by the fluid sample and asecond end positioned to emit the received fluorescence light toward thesecond sensor position.